1. Field of the Invention
The present invention provides an optical module, and more particularly, an optical module using a linear sensor for identifying images.
2. Description of the Prior Art
Fingerprint identification systems have been widely used in fields of personal identification, safe deposits, vehicles, entrance systems, automatic teller machines, network security systems, etc. A prior art identification system checks a user's status based on an card, while the fingerprint identification systems is based on fingerprints, so that the fingerprint identification systems can increase security of personal identification.
Please refer to FIG. 1, which illustrates a schematic diagram of a prior art optical module 1 of a fingerprint identification system. The optical module 1 includes a light source 12, a sensor 14, a reflector 18, a prism 16, and a circuit board 10. The light source 12 and the sensor 14 are installed on the circuit board 10.
When a user puts a fingerprint on a position shown in FIG. 1, the light source 12 emits light through the prism 16 to the fingerprint. Then, the prism 16 totally reflects reflection of the fingerprint to the reflector 18 for reflecting the reflection of the fingerprint to the sensor 14, so as to sense the fingerprint.
The optical module 1 must use two optical elements, one is reflector 18, and the other is the prism 16. Owing to placement of the optical elements, the optical module 1 cannot be utilized in small electronic devices, such as mobile phones, and is not facile to be fabricated.